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761.
Benign esophagorespiratory fistulas in adults 总被引:2,自引:0,他引:2
Four benign esophagorespiratory fistulas, three secondary to granulomatous disease and one presumed to be congenital, have been diagnosed in adults at the authors' institution in the past year. The patients had symptoms of chronic or recurrent pulmonary infections, and two experienced coughing after swallowing. Chest radiographs demonstrated refractory consolidation, with or without cavitation and frequently accompanied by an air-distended esophagus. Barium studies were diagnostic. All patients responded well to antibiotic and surgical therapy. 相似文献
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764.
Pulmonary abnormalities and PET data analysis: a retrospective study 总被引:13,自引:0,他引:13
Lowe VJ; Duhaylongsod FG; Patz EF; Delong DM; Hoffman JM; Wolfe WG; Coleman RE 《Radiology》1997,202(2):435
765.
Gamma camera radionuclide images: improved contrast with energy- weighted acquisition 总被引:4,自引:0,他引:4
An energy-weighted acquisition (EWA) technique has been developed that utilizes all scintillation events, weighting their contributions depending on their energy, to formulate a radionuclide image. Photopeak events from primary radiation contribute positively; scatter events contribute negatively, providing for scatter subtraction and improved image contrast. EWA is employed with an on-line weighted-acquisition module (WAM) as the data are acquired, rather than as a postprocessing technique. EWA was compared with normal window imaging in patients and in phantoms. For gallium-67 and thallium-201, contrast improved by as much as 40%. A much smaller improvement in contrast was observed with technetium-99m due to its ideal monoenergetic emissions. Single photon emission computed tomographic studies also showed improved contrast and were without artifact. EWA has great promise, and with further development quantitative scatter correction may be possible. 相似文献
766.
In the present study we investigate the nature of the murine bone marrow cell subset responsible for the marked increase in histamine synthesis induced by interleukin-3 (IL-3). Because mast cells, and eventually their committed precursors, represent a potential source of histamine in this context, we examined their possible participation in this biologic activity with particular attention. We provide evidence that neither of these populations respond to IL-3 in terms of histamine synthesis and that other differentiated end cells or stromal components of the bone marrow are also not involved in this phenomenon. Starting from these findings, we further characterized the immature hematopoietic compartment responsible for IL-3-induced histamine synthesis using fluorescence-activated cell sorter (FACS) sorting based on rhodamine retention or wheat germ agglutinin (WGA) affinity. These procedures have allowed us to ascribe the following features to histamine-producing cells: (1) They belong to a low-density, progenitor- enriched bone marrow subset containing cells of relatively important size and internal structure. (2) The highest histamine levels are generated by the rhodamine-bright fraction of this population, while the most primitive rhodamine-dull cells do not express this biologic activity. (3) Histamine-producing cells do not copurify with colony- forming units in spleen day 7 and day 12 in WGA-bright fractions. (4) Their enrichment is associated with increased frequencies of cells forming colonies in methylcellulose (CFU-C), suggesting the involvement of several progenitors with partially limited differentiation potential in this biologic activity. 相似文献
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768.
A linear attenuation coefficient for water (mu = .15 cm-1) at 140 keV has been used in the determination of left ventricular volumes (LVV) by attenuation-corrected equilibrium methods. This theoretical value ignores the effect of Compton scatter and thus may be too high for human LVV determinations. The effective attenuation coefficient, mu', of the human chest was determined in ten normal volunteers using a Tc-99m esophageal source imaged with a gamma camera. Values for mu' at 30 degrees LAO in end-expiration, quiet breathing, and end-inspiration were .125 +/- .006 cm-1, .125 +/- .005 cm-1, and .113 +/- .007 cm-1, respectively (95% confidence interval). Values of mu' at 45 degrees LAO were .122 +/- .006 cm-1, .119 +/- .007 cm-1, and .099 +/- .009 cm-1, respectively, for the same conditions. The measured value of mu' for the source in a water phantom was .127 +/- .001 cm-1. This suggests that a value of mu' of .125 cm-1 may be appropriate for use in determining LVV in patients. 相似文献
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J.R. Juttmann J.C.W. Hagenouw-Taal L.D.F. Lameyer A.M. Ruis J.C. Birkenhäger 《Metabolism: clinical and experimental》1979,28(11):1114-1121
In 14 nondialyzed patients with chronic renal failure (CRF) and at the start of treatment a glomerular filtration rate (GFR) of 14--47 ml/min changes in bone mineral mass (BMM), expressed in percentage of the initial value, showed a significant correlation with the mean GFR during an observation period of 16 +/- 2 mo. During a predialysis period of 6 mo BMM decreased to 97.8 +/- 3.2% of the original value in 9 patients, while after 6, 12, and 16 mo of dialysis treatment, BMM in the same patients fell to 94.5 +/- 3.0%, 92.0 +/- 3.2% and 91.8 +/- 4.6% of the initial value. As after the onset of regular hemodialysis the fractional intestinal absorption of 47Ca does not decrease but even increases in most patients, the importance of the level of intestinal calcium absorption for the development of dialysis bone disease may be questioned. 相似文献